An unshielded radio-frequency atomic magnetometer with sub-femtoTesla sensitivity
Abstract
We demonstrate a radio-frequency potassium-vapor magnetometer operating with sensitivities of 0.3 fT/Hz at 0.5 MHz and 0.9 fT/Hz at 1.31 MHz in the absence of radio-frequency and mu-metal or magnetic shielding. The use of spatially separated magnetometers, two voxels within the same cell, permits for the subtraction of common mode noise and the retention of a gradient signal, as from a local source. At 0.5 MHz the common mode noise was white and measured to be 3.4 fT/Hz; upon subtraction the noise returned to the values observed when the magnetometer was shielded. At 1.31 MHz, the common mode noise was from a nearby radio station and was reduced by a factor of 33 upon subtraction, limited only by the radio signal picked up by receiver electronics. Potential applications include in-the-field low-field magnetic resonance, such as the use of nuclear quadrupole resonance for the detection of explosives.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 01, 2014
- Source ID
- 10.1063/1.4905449
Entities
People
- Adam W. Conovaloff
- David A. Keder
- David W. Prescott
- Karen L. Sauer
Organizations
- Defense Advanced Research Projects Agency
- George Mason University
- National Science Foundation